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                    第2章 线程管理
            
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                    2.1 线程的基本操作
            
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                    2.2 传递参数
            
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                    2.3 转移所有权
            
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                    2.4 确定线程数量
            
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                    2.5 线程标识
            
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                    2.6 本章总结
            
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                    第3章 共享数据
            
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                    3.1 共享数据的问题
            
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                    3.2 使用互斥量
            
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                    3.3 保护共享数据的方式
            
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                    3.4 本章总结
            
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                    第4章 同步操作
            
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                    4.1 等待事件或条件
            
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                    4.2 使用future
            
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                    4.3 限时等待
            
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                    4.4 简化代码
            
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                    4.5 本章总结
            
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                    第5章 内存模型和原子操作
            
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                    5.1 内存模型
            
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                    5.2 原子操作和原子类型
            
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                    5.3 同步操作和强制排序
            
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                    5.4 本章总结
            
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                    第6章 设计基于锁的并发数据结构
            
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                    6.1 并发设计的意义
            
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                    6.2 基于锁的并发数据结构
            
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                    6.3 设计更加复杂的数据结构
            
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                    6.4 本章总结
            
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                    第7章 设计无锁的并发数据结构
            
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                    7.1 定义和意义
            
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                    7.2 无锁数据结构的例子
            
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                    7.3 设计无锁数据结构的指导建议
            
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                    7.4 本章总结
            
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        <li class="chapter " data-level="1.15" data-path="../chapter8/8.0-chinese.html">
            
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                    第8章 并发设计
            
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                    8.1 线程间划分工作
            
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                    8.2 并发代码的性能
            
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                    8.3 为多线程性能设计数据结构
            
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                    8.4 设计并发代码的注意事项
            
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                    8.5 在实践中设计并发代码
            
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                    8.6 本章总结
            
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                    第9章 高级线程管理
            
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                    9.1 线程池
            
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                    9.2 中断线程
            
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                    9.3 本章总结
            
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                    第10章 并行算法
            
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        <li class="chapter " data-level="1.17.1" data-path="../chapter10/10.1-chinese.html">
            
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                    10.1 并行化标准库算法
            
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        <li class="chapter " data-level="1.17.2" data-path="../chapter10/10.2-chinese.html">
            
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                    10.2 执行策略
            
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        <li class="chapter " data-level="1.17.3" data-path="../chapter10/10.3-chinese.html">
            
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                    10.3 C++标准库中的并行算法
            
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                    10.4 本章总结
            
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        <li class="chapter " data-level="1.18" data-path="../chapter11/11.0-chinese.html">
            
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                    第11章 测试和调试多线程应用
            
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        <li class="chapter " data-level="1.18.1" data-path="../chapter11/11.1-chinese.html">
            
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                    11.1 与并发相关的Bug
            
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        <li class="chapter " data-level="1.18.2" data-path="../chapter11/11.2-chinese.html">
            
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                    11.2 定位并发Bug的技巧
            
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        <li class="chapter " data-level="1.18.3" data-path="../chapter11/11.3-chinese.html">
            
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                    11.3 本章总结
            
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        <li class="chapter " data-level="1.19" data-path="A.0-chinese.html">
            
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                    附录A C++11特性简明参考(部分)
            
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        <li class="chapter " data-level="1.19.1" data-path="A.1-chinese.html">
            
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                    A.1 右值引用
            
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        <li class="chapter " data-level="1.19.2" data-path="A.2-chinese.html">
            
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                    A.2 删除函数
            
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        <li class="chapter " data-level="1.19.3" data-path="A.3-chinese.html">
            
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                    A.3 默认函数
            
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        <li class="chapter " data-level="1.19.4" data-path="A.4-chinese.html">
            
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                    A.4 常量表达式函数
            
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        <li class="chapter " data-level="1.19.5" data-path="A.5-chinese.html">
            
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                    A.5 Lambda函数
            
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        <li class="chapter active" data-level="1.19.6" data-path="A.6-chinese.html">
            
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                    A.6 变参模板
            
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        <li class="chapter " data-level="1.19.7" data-path="A.7-chinese.html">
            
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                    A.7 自动推导变量类型
            
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        <li class="chapter " data-level="1.19.8" data-path="A.8-chinese.html">
            
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                    A.8 线程本地变量
            
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        <li class="chapter " data-level="1.19.9" data-path="A.9-chinese.html">
            
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                    A.9 模板类参数的推导
            
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        <li class="chapter " data-level="1.19.10" data-path="A.10-chinese.html">
            
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                    A.10 本章总结
            
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        <li class="chapter " data-level="1.20" data-path="../appendix_B/B.0-chinese.html">
            
                <a href="../appendix_B/B.0-chinese.html">
            
                    
                    附录B 并发库简要对比
            
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        <li class="chapter " data-level="1.21" data-path="../appendix_C/C.0-chinese.html">
            
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                    附录C 消息传递框架与完整的ATM示例
            
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                    附录D C++线程类库参考
            
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                    D.2 condition_variable头文件
            
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                    D.3 atomic头文件
            
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                                <section class="normal markdown-section">
                                
                                <h1 id="a6-&#x53D8;&#x53C2;&#x6A21;&#x677F;">A.6 &#x53D8;&#x53C2;&#x6A21;&#x677F;</h1>
<p>&#x53D8;&#x53C2;&#x6A21;&#x677F;&#xFF1A;&#x5C31;&#x662F;&#x53EF;&#x4EE5;&#x4F7F;&#x7528;&#x4E0D;&#x5B9A;&#x6570;&#x91CF;&#x7684;&#x53C2;&#x6570;&#x8FDB;&#x884C;&#x7279;&#x5316;&#x7684;&#x6A21;&#x677F;&#x3002;&#x5C31;&#x50CF;&#x4F60;&#x63A5;&#x89E6;&#x5230;&#x7684;&#x53D8;&#x53C2;&#x51FD;&#x6570;&#x4E00;&#x6837;&#xFF0C;printf&#x5C31;&#x63A5;&#x53D7;&#x53EF;&#x53D8;&#x53C2;&#x6570;&#x3002;&#x73B0;&#x5728;&#xFF0C;&#x5C31;&#x53EF;&#x4EE5;&#x7ED9;&#x4F60;&#x7684;&#x6A21;&#x677F;&#x6307;&#x5B9A;&#x4E0D;&#x5B9A;&#x6570;&#x91CF;&#x7684;&#x53C2;&#x6570;&#x4E86;&#x3002;&#x53D8;&#x53C2;&#x6A21;&#x677F;&#x5728;&#x6574;&#x4E2A;<code>C++</code>&#x7EBF;&#x7A0B;&#x5E93;&#x4E2D;&#x90FD;&#x6709;&#x4F7F;&#x7528;&#xFF0C;&#x4F8B;&#x5982;&#xFF1A;<code>std::thread</code>&#x7684;&#x6784;&#x9020;&#x51FD;&#x6570;&#x5C31;&#x662F;&#x4E00;&#x4E2A;&#x53D8;&#x53C2;&#x7C7B;&#x6A21;&#x677F;&#x3002;&#x4ECE;&#x4F7F;&#x7528;&#x8005;&#x7684;&#x89D2;&#x5EA6;&#x770B;&#xFF0C;&#x4EC5;&#x77E5;&#x9053;&#x6A21;&#x677F;&#x53EF;&#x4EE5;&#x63A5;&#x53D7;&#x65E0;&#x9650;&#x4E2A;&#x53C2;&#x6570;&#x5C31;&#x591F;&#x4E86;&#xFF0C;&#x4E0D;&#x8FC7;&#x5F53;&#x8981;&#x5199;&#x4E00;&#x4E2A;&#x6A21;&#x677F;&#x6216;&#x5BF9;&#x5176;&#x5DE5;&#x4F5C;&#x539F;&#x7406;&#x5F88;&#x611F;&#x5174;&#x8DA3;&#x5C31;&#x9700;&#x8981;&#x4E86;&#x89E3;&#x4E00;&#x4E9B;&#x7EC6;&#x8282;&#x3002;</p>
<p>&#x548C;&#x53D8;&#x53C2;&#x51FD;&#x6570;&#x4E00;&#x6837;&#xFF0C;&#x53D8;&#x53C2;&#x90E8;&#x5206;&#x53EF;&#x4EE5;&#x5728;&#x53C2;&#x6570;&#x5217;&#x8868;&#x7AE0;&#x4F7F;&#x7528;&#x7701;&#x7565;&#x53F7;<code>...</code>&#x4EE3;&#x8868;&#xFF0C;&#x53D8;&#x53C2;&#x6A21;&#x677F;&#x9700;&#x8981;&#x5728;&#x53C2;&#x6570;&#x5217;&#x8868;&#x4E2D;&#x4F7F;&#x7528;&#x7701;&#x7565;&#x53F7;&#xFF1A;</p>
<pre><code class="lang-c++"><span class="hljs-keyword">template</span>&lt;<span class="hljs-keyword">typename</span> ... ParameterPack&gt;
<span class="hljs-keyword">class</span> my_template
{};
</code></pre>
<p>&#x5373;&#x4F7F;&#x4E3B;&#x6A21;&#x677F;&#x4E0D;&#x662F;&#x53D8;&#x53C2;&#x6A21;&#x677F;&#xFF0C;&#x6A21;&#x677F;&#x8FDB;&#x884C;&#x90E8;&#x5206;&#x7279;&#x5316;&#x7684;&#x7C7B;&#x4E2D;&#xFF0C;&#x4E5F;&#x53EF;&#x4EE5;&#x4F7F;&#x7528;&#x53EF;&#x53D8;&#x53C2;&#x6570;&#x6A21;&#x677F;&#x3002;&#x4F8B;&#x5982;&#xFF0C;<code>std::packaged_task&lt;&gt;</code>(&#x89C1;4.2.1&#x8282;)&#x7684;&#x4E3B;&#x6A21;&#x677F;&#x5C31;&#x662F;&#x4E00;&#x4E2A;&#x7B80;&#x5355;&#x7684;&#x6A21;&#x677F;&#xFF0C;&#x8FD9;&#x4E2A;&#x7B80;&#x5355;&#x7684;&#x6A21;&#x677F;&#x53EA;&#x6709;&#x4E00;&#x4E2A;&#x53C2;&#x6570;&#xFF1A;</p>
<pre><code class="lang-c++"><span class="hljs-keyword">template</span>&lt;<span class="hljs-keyword">typename</span> FunctionType&gt;
<span class="hljs-keyword">class</span> packaged_task;
</code></pre>
<p>&#x4E0D;&#x8FC7;&#xFF0C;&#x5E76;&#x4E0D;&#x662F;&#x6240;&#x6709;&#x5730;&#x65B9;&#x90FD;&#x8FD9;&#x6837;&#x5B9A;&#x4E49;&#x3002;&#x5BF9;&#x4E8E;&#x90E8;&#x5206;&#x7279;&#x5316;&#x6A21;&#x677F;&#x6765;&#x8BF4;&#x50CF;&#x662F;&#x4E00;&#x4E2A;&#x201C;&#x5360;&#x4F4D;&#x7B26;&#x201D;&#xFF1A;</p>
<pre><code class="lang-c++"><span class="hljs-keyword">template</span>&lt;<span class="hljs-keyword">typename</span> ReturnType,<span class="hljs-keyword">typename</span> ... Args&gt;
<span class="hljs-keyword">class</span> packaged_task&lt;ReturnType(Args...)&gt;;
</code></pre>
<p>&#x90E8;&#x5206;&#x7279;&#x5316;&#x7684;&#x7C7B;&#x5C31;&#x5305;&#x542B;&#x5B9E;&#x9645;&#x5B9A;&#x4E49;&#x7684;&#x7C7B;&#x3002;&#x5728;&#x7B2C;4&#x7AE0;&#xFF0C;&#x53EF;&#x4EE5;&#x5199;&#x4E00;&#x4E2A;<code>std::packaged_task&lt;int(std::string,double)&gt;</code>&#x6765;&#x58F0;&#x660E;&#x4E00;&#x4E2A;&#x4EE5;<code>std::string</code>&#x548C;double&#x4F5C;&#x4E3A;&#x53C2;&#x6570;&#x7684;&#x4EFB;&#x52A1;&#xFF0C;&#x5F53;&#x6267;&#x884C;&#x8FD9;&#x4E2A;&#x4EFB;&#x52A1;&#x540E;&#x7ED3;&#x679C;&#x4F1A;&#x7531;<code>std::future&lt;int&gt;</code>&#x8FDB;&#x884C;&#x4FDD;&#x5B58;&#x3002;</p>
<p>&#x58F0;&#x660E;&#x5C55;&#x793A;&#x4E86;&#x4E24;&#x4E2A;&#x53D8;&#x53C2;&#x6A21;&#x677F;&#x7684;&#x9644;&#x52A0;&#x7279;&#x6027;&#x3002;&#x7B2C;&#x4E00;&#x4E2A;&#x6BD4;&#x8F83;&#x7B80;&#x5355;&#xFF1A;&#x666E;&#x901A;&#x6A21;&#x677F;&#x53C2;&#x6570;(&#x4F8B;&#x5982;ReturnType)&#x548C;&#x53EF;&#x53D8;&#x6A21;&#x677F;&#x53C2;&#x6570;(Args)&#x53EF;&#x4EE5;&#x540C;&#x65F6;&#x58F0;&#x660E;&#x3002;&#x7B2C;&#x4E8C;&#x4E2A;&#x7279;&#x6027;&#xFF0C;&#x5C55;&#x793A;&#x4E86;<code>Args...</code>&#x7279;&#x5316;&#x7C7B;&#x7684;&#x6A21;&#x677F;&#x53C2;&#x6570;&#x5217;&#x8868;&#x4E2D;&#x5982;&#x4F55;&#x4F7F;&#x7528;&#xFF0C;&#x4E3A;&#x4E86;&#x5C55;&#x793A;&#x5B9E;&#x4F8B;&#x5316;&#x6A21;&#x677F;&#x4E2D;&#x7684;Args&#x7684;&#x7EC4;&#x6210;&#x7C7B;&#x578B;&#x3002;&#x5B9E;&#x9645;&#x4E0A;&#xFF0C;&#x56E0;&#x4E3A;&#x662F;&#x90E8;&#x5206;&#x7279;&#x5316;&#xFF0C;&#x6240;&#x4EE5;&#x5176;&#x4F5C;&#x4E3A;&#x4E00;&#x79CD;&#x6A21;&#x5F0F;&#x8FDB;&#x884C;&#x5339;&#x914D;&#x3002;&#x5728;&#x5217;&#x8868;&#x4E2D;&#x51FA;&#x73B0;&#x7684;&#x7C7B;&#x578B;(&#x88AB;Args&#x6355;&#x83B7;)&#x90FD;&#x4F1A;&#x8FDB;&#x884C;&#x5B9E;&#x4F8B;&#x5316;&#x3002;&#x53C2;&#x6570;&#x5305;(parameter pack)&#x8C03;&#x7528;&#x53EF;&#x53D8;&#x53C2;&#x6570;Args&#xFF0C;&#x5E76;&#x4E14;&#x4F7F;&#x7528;<code>Args...</code>&#x4F5C;&#x4E3A;&#x5305;&#x7684;&#x6269;&#x5C55;&#x3002;</p>
<p>&#x548C;&#x53EF;&#x53D8;&#x53C2;&#x51FD;&#x6570;&#x4E00;&#x6837;&#xFF0C;&#x53D8;&#x53C2;&#x90E8;&#x5206;&#x53EF;&#x80FD;&#x4EC0;&#x4E48;&#x90FD;&#x6CA1;&#x6709;&#xFF0C;&#x4E5F;&#x53EF;&#x80FD;&#x6709;&#x5F88;&#x591A;&#x7C7B;&#x578B;&#x9879;&#x3002;&#x4F8B;&#x5982;&#xFF0C;<code>std::packaged_task&lt;my_class()&gt;</code>&#x4E2D;ReturnType&#x53C2;&#x6570;&#x5C31;&#x662F;my_class&#xFF0C;&#x5E76;&#x4E14;Args&#x53C2;&#x6570;&#x5305;&#x662F;&#x7A7A;&#x7684;&#xFF0C;&#x4E0D;&#x8FC7;<code>std::packaged_task&lt;void(int,double,my_class&amp;,std::string*)&gt;</code>&#x4E2D;&#xFF0C;ReturnType&#x4E3A;void&#xFF0C;&#x5E76;&#x4E14;Args&#x5217;&#x8868;&#x4E2D;&#x7684;&#x7C7B;&#x578B;&#x5C31;&#x6709;&#xFF1A;int, double, my_class&amp;&#x548C;std::string*&#x3002;</p>
<h2 id="a61-&#x6269;&#x5C55;&#x53C2;&#x6570;&#x5305;">A.6.1 &#x6269;&#x5C55;&#x53C2;&#x6570;&#x5305;</h2>
<p>&#x53D8;&#x53C2;&#x6A21;&#x677F;&#x4E3B;&#x8981;&#x4F9D;&#x8D56;&#x6269;&#x5C55;&#x529F;&#x80FD;&#xFF0C;&#x56E0;&#x4E3A;&#x4E0D;&#x80FD;&#x9650;&#x5236;&#x6709;&#x66F4;&#x591A;&#x7684;&#x7C7B;&#x578B;&#x6DFB;&#x52A0;&#x5230;&#x6A21;&#x677F;&#x53C2;&#x6570;&#x4E2D;&#x3002;&#x9996;&#x5148;&#xFF0C;&#x5217;&#x8868;&#x4E2D;&#x7684;&#x53C2;&#x6570;&#x7C7B;&#x578B;&#x4F7F;&#x7528;&#x5230;&#x7684;&#x65F6;&#x5019;&#xFF0C;&#x53EF;&#x4EE5;&#x4F7F;&#x7528;&#x5305;&#x6269;&#x5C55;&#xFF0C;&#x6BD4;&#x5982;&#xFF1A;&#x9700;&#x8981;&#x7ED9;&#x5176;&#x4ED6;&#x6A21;&#x677F;&#x63D0;&#x4F9B;&#x7C7B;&#x578B;&#x53C2;&#x6570;&#x3002;</p>
<pre><code class="lang-c++"><span class="hljs-keyword">template</span>&lt;<span class="hljs-keyword">typename</span> ... Params&gt;
<span class="hljs-keyword">struct</span> dummy
{
  <span class="hljs-built_in">std</span>::tuple&lt;Params...&gt; data;
};
</code></pre>
<p>&#x6210;&#x5458;&#x53D8;&#x91CF;data&#x662F;&#x4E00;&#x4E2A;<code>std::tuple&lt;&gt;</code>&#x5B9E;&#x4F8B;&#xFF0C;&#x5305;&#x542B;&#x6240;&#x6709;&#x6307;&#x5B9A;&#x7C7B;&#x578B;&#xFF0C;&#x6240;&#x4EE5;dummy<int, double,="" char="">&#x7684;&#x6210;&#x5458;&#x53D8;&#x91CF;&#x5C31;&#x4E3A;<code>std::tuple&lt;int, double, char&gt;</code>&#x3002;&#x53EF;&#x4EE5;&#x5C06;&#x5305;&#x6269;&#x5C55;&#x548C;&#x666E;&#x901A;&#x7C7B;&#x578B;&#x76F8;&#x7ED3;&#x5408;&#xFF1A;</int,></p>
<pre><code class="lang-c++"><span class="hljs-keyword">template</span>&lt;<span class="hljs-keyword">typename</span> ... Params&gt;
<span class="hljs-keyword">struct</span> dummy2
{
  <span class="hljs-built_in">std</span>::tuple&lt;<span class="hljs-built_in">std</span>::<span class="hljs-built_in">string</span>,Params...&gt; data;
};
</code></pre>
<p>&#x8FD9;&#x6B21;&#xFF0C;&#x5143;&#x7EC4;&#x4E2D;&#x6DFB;&#x52A0;&#x4E86;&#x989D;&#x5916;&#x7684;(&#x7B2C;&#x4E00;&#x4E2A;)&#x6210;&#x5458;&#x7C7B;&#x578B;<code>std::string</code>&#x3002;&#x5176;&#x4F18;&#x96C5;&#x4E4B;&#x5904;&#x5728;&#x4E8E;&#xFF0C;&#x53EF;&#x4EE5;&#x901A;&#x8FC7;&#x5305;&#x6269;&#x5C55;&#x7684;&#x65B9;&#x5F0F;&#x521B;&#x5EFA;&#x4E00;&#x79CD;&#x6A21;&#x5F0F;&#xFF0C;&#x8FD9;&#x79CD;&#x6A21;&#x5F0F;&#x4F1A;&#x5728;&#x4E4B;&#x540E;&#x5C06;&#x6BCF;&#x4E2A;&#x5143;&#x7D20;&#x62F7;&#x8D1D;&#x5230;&#x6269;&#x5C55;&#x4E4B;&#x4E2D;&#xFF0C;&#x53EF;&#x4EE5;&#x4F7F;&#x7528;<code>...</code>&#x6765;&#x8868;&#x793A;&#x6269;&#x5C55;&#x6A21;&#x5F0F;&#x7684;&#x7ED3;&#x675F;&#x3002;&#x4F8B;&#x5982;&#xFF0C;&#x521B;&#x5EFA;&#x4F7F;&#x7528;&#x53C2;&#x6570;&#x5305;&#x6765;&#x521B;&#x5EFA;&#x5143;&#x7EC4;&#x4E2D;&#x6240;&#x6709;&#x7684;&#x5143;&#x7D20;&#xFF0C;&#x4E0D;&#x5982;&#x5728;&#x5143;&#x7EC4;&#x4E2D;&#x521B;&#x5EFA;&#x6307;&#x9488;&#xFF0C;&#x6216;&#x4F7F;&#x7528;<code>std::unique_ptr&lt;&gt;</code>&#x6307;&#x9488;&#xFF0C;&#x6307;&#x5411;&#x5BF9;&#x5E94;&#x5143;&#x7D20;&#xFF1A;</p>
<pre><code class="lang-c++"><span class="hljs-keyword">template</span>&lt;<span class="hljs-keyword">typename</span> ... Params&gt;
<span class="hljs-keyword">struct</span> dummy3
{
  <span class="hljs-built_in">std</span>::tuple&lt;Params* ...&gt; pointers;
  <span class="hljs-built_in">std</span>::tuple&lt;<span class="hljs-built_in">std</span>::<span class="hljs-built_in">unique_ptr</span>&lt;Params&gt; ...&gt; unique_pointers;
};
</code></pre>
<p>&#x7C7B;&#x578B;&#x8868;&#x8FBE;&#x5F0F;&#x4F1A;&#x6BD4;&#x8F83;&#x590D;&#x6742;&#xFF0C;&#x63D0;&#x4F9B;&#x7684;&#x53C2;&#x6570;&#x5305;&#x662F;&#x5728;&#x7C7B;&#x578B;&#x8868;&#x8FBE;&#x5F0F;&#x4E2D;&#x4EA7;&#x751F;&#xFF0C;&#x5E76;&#x4E14;&#x8868;&#x8FBE;&#x5F0F;&#x4E2D;&#x4F7F;&#x7528;<code>...</code>&#x4F5C;&#x4E3A;&#x6269;&#x5C55;&#x3002;&#x5F53;&#x53C2;&#x6570;&#x5305;&#x5DF2;&#x7ECF;&#x6269;&#x5C55; &#xFF0C;&#x5305;&#x4E2D;&#x7684;&#x6BCF;&#x4E00;&#x9879;&#x90FD;&#x4F1A;&#x4EE3;&#x66FF;&#x5BF9;&#x5E94;&#x7684;&#x7C7B;&#x578B;&#x8868;&#x8FBE;&#x5F0F;&#xFF0C;&#x5728;&#x7ED3;&#x679C;&#x5217;&#x8868;&#x4E2D;&#x4EA7;&#x751F;&#x76F8;&#x5E94;&#x7684;&#x6570;&#x636E;&#x9879;&#x3002;&#x56E0;&#x6B64;&#xFF0C;&#x5F53;&#x53C2;&#x6570;&#x5305;Params&#x5305;&#x542B;int&#xFF0C;int&#xFF0C;char&#x7C7B;&#x578B;&#xFF0C;&#x90A3;&#x4E48;<code>std::tuple&lt;std::pair&lt;std::unique_ptr&lt;Params&gt;,double&gt; ... &gt;</code>&#x5C06;&#x6269;&#x5C55;&#x4E3A;<code>std::tuple&lt;std::pair&lt;std::unique_ptr&lt;int&gt;,double&gt;</code>,<code>std::pair&lt;std::unique_ptr&lt;int&gt;,double&gt;</code>,<code>std::pair&lt;std::unique_ptr&lt;char&gt;, double&gt; &gt;</code>&#x3002;&#x5982;&#x679C;&#x5305;&#x6269;&#x5C55;&#x5F53;&#x505A;&#x6A21;&#x677F;&#x53C2;&#x6570;&#x5217;&#x8868;&#x4F7F;&#x7528;&#x65F6;&#xFF0C;&#x6A21;&#x677F;&#x5C31;&#x4E0D;&#x9700;&#x8981;&#x53D8;&#x957F;&#x7684;&#x53C2;&#x6570;&#x4E86;&#x3002;&#x5982;&#x679C;&#x4E0D;&#x9700;&#x8981;&#x4E86;&#xFF0C;&#x53C2;&#x6570;&#x5305;&#x5C31;&#x8981;&#x5BF9;&#x6A21;&#x677F;&#x53C2;&#x6570;&#x7684;&#x8981;&#x6C42;&#x8FDB;&#x884C;&#x51C6;&#x786E;&#x7684;&#x5339;&#x914D;&#xFF1A;</p>
<pre><code class="lang-c++"><span class="hljs-keyword">template</span>&lt;<span class="hljs-keyword">typename</span> ... Types&gt;
<span class="hljs-keyword">struct</span> dummy4
{
  <span class="hljs-built_in">std</span>::pair&lt;Types...&gt; data;
};
dummy4&lt;<span class="hljs-keyword">int</span>,<span class="hljs-keyword">char</span>&gt; a;  <span class="hljs-comment">// 1 ok&#xFF0C;&#x4E3A;std::pair&lt;int, char&gt;</span>
dummy4&lt;<span class="hljs-keyword">int</span>&gt; b;  <span class="hljs-comment">// 2 &#x9519;&#x8BEF;&#xFF0C;&#x65E0;&#x7B2C;&#x4E8C;&#x4E2A;&#x7C7B;&#x578B;</span>
dummy4&lt;<span class="hljs-keyword">int</span>,<span class="hljs-keyword">int</span>,<span class="hljs-keyword">int</span>&gt; c;  <span class="hljs-comment">// 3 &#x9519;&#x8BEF;&#xFF0C;&#x7C7B;&#x578B;&#x592A;&#x591A;</span>
</code></pre>
<p>&#x53EF;&#x4EE5;&#x4F7F;&#x7528;&#x5305;&#x6269;&#x5C55;&#x7684;&#x65B9;&#x5F0F;&#xFF0C;&#x5BF9;&#x51FD;&#x6570;&#x7684;&#x53C2;&#x6570;&#x8FDB;&#x884C;&#x58F0;&#x660E;&#xFF1A;</p>
<pre><code class="lang-c++"><span class="hljs-keyword">template</span>&lt;<span class="hljs-keyword">typename</span> ... Args&gt;
<span class="hljs-function"><span class="hljs-keyword">void</span> <span class="hljs-title">foo</span><span class="hljs-params">(Args ... args)</span></span>;
</code></pre>
<p>&#x8FD9;&#x5C06;&#x4F1A;&#x521B;&#x5EFA;&#x4E00;&#x4E2A;&#x65B0;&#x53C2;&#x6570;&#x5305;args&#xFF0C;&#x5176;&#x662F;&#x4E00;&#x7EC4;&#x51FD;&#x6570;&#x53C2;&#x6570;&#xFF0C;&#x800C;&#x975E;&#x4E00;&#x7EC4;&#x7C7B;&#x578B;&#xFF0C;&#x5E76;&#x4E14;&#x8FD9;&#x91CC;<code>...</code>&#x4E5F;&#x80FD;&#x50CF;&#x4E4B;&#x524D;&#x4E00;&#x6837;&#x8FDB;&#x884C;&#x6269;&#x5C55;&#x3002;&#x4F8B;&#x5982;&#xFF0C;&#x53EF;&#x4EE5;&#x5728;<code>std::thread</code>&#x7684;&#x6784;&#x9020;&#x51FD;&#x6570;&#x4E2D;&#x4F7F;&#x7528;&#xFF0C;&#x4F7F;&#x7528;&#x53F3;&#x503C;&#x5F15;&#x7528;&#x7684;&#x65B9;&#x5F0F;&#x83B7;&#x53D6;&#x51FD;&#x6570;&#x6240;&#x6709;&#x7684;&#x53C2;&#x6570;(&#x89C1;A.1&#x8282;)&#xFF1A;</p>
<pre><code class="lang-c++"><span class="hljs-keyword">template</span>&lt;<span class="hljs-keyword">typename</span> CallableType,<span class="hljs-keyword">typename</span> ... Args&gt;
thread::thread(CallableType&amp;&amp; func,Args&amp;&amp; ... args);
</code></pre>
<p>&#x51FD;&#x6570;&#x53C2;&#x6570;&#x5305;&#x4E5F;&#x53EF;&#x4EE5;&#x7528;&#x6765;&#x8C03;&#x7528;&#x5176;&#x4ED6;&#x51FD;&#x6570;&#xFF0C;&#x5C06;&#x5236;&#x5B9A;&#x5305;&#x6269;&#x5C55;&#x6210;&#x53C2;&#x6570;&#x5217;&#x8868;&#xFF0C;&#x5339;&#x914D;&#x8C03;&#x7528;&#x7684;&#x51FD;&#x6570;&#x3002;&#x5982;&#x540C;&#x7C7B;&#x578B;&#x6269;&#x5C55;&#x4E00;&#x6837;&#xFF0C;&#x4E5F;&#x53EF;&#x4EE5;&#x4F7F;&#x7528;&#x67D0;&#x79CD;&#x6A21;&#x5F0F;&#x5BF9;&#x53C2;&#x6570;&#x5217;&#x8868;&#x8FDB;&#x884C;&#x6269;&#x5C55;&#x3002;&#x4F8B;&#x5982;&#xFF0C;&#x4F7F;&#x7528;<code>std::forward()</code>&#x4EE5;&#x53F3;&#x503C;&#x5F15;&#x7528;&#x7684;&#x65B9;&#x5F0F;&#x6765;&#x4FDD;&#x5B58;&#x63D0;&#x4F9B;&#x7ED9;&#x51FD;&#x6570;&#x7684;&#x53C2;&#x6570;&#xFF1A;</p>
<pre><code class="lang-c++"><span class="hljs-keyword">template</span>&lt;<span class="hljs-keyword">typename</span> ... ArgTypes&gt;
<span class="hljs-function"><span class="hljs-keyword">void</span> <span class="hljs-title">bar</span><span class="hljs-params">(ArgTypes&amp;&amp; ... args)</span>
</span>{
  foo(<span class="hljs-built_in">std</span>::forward&lt;ArgTypes&gt;(args)...);
}
</code></pre>
<p>&#x6CE8;&#x610F;&#x4E00;&#x4E0B;&#x8FD9;&#x4E2A;&#x4F8B;&#x5B50;&#xFF0C;&#x5305;&#x6269;&#x5C55;&#x5305;&#x62EC;&#x5BF9;&#x7C7B;&#x578B;&#x5305;ArgTypes&#x548C;&#x51FD;&#x6570;&#x53C2;&#x6570;&#x5305;args&#x7684;&#x6269;&#x5C55;&#xFF0C;&#x5E76;&#x4E14;&#x7701;&#x7565;&#x4E86;&#x5176;&#x4F59;&#x7684;&#x8868;&#x8FBE;&#x5F0F;&#x3002;&#x5F53;&#x8FD9;&#x6837;&#x8C03;&#x7528;bar&#x51FD;&#x6570;&#xFF1A;</p>
<pre><code class="lang-c++"><span class="hljs-keyword">int</span> i;
bar(i,<span class="hljs-number">3.141</span>,<span class="hljs-built_in">std</span>::<span class="hljs-built_in">string</span>(<span class="hljs-string">&quot;hello &quot;</span>));
</code></pre>
<p>&#x5C06;&#x4F1A;&#x6269;&#x5C55;&#x4E3A;</p>
<pre><code class="lang-c++"><span class="hljs-keyword">template</span>&lt;&gt;
<span class="hljs-keyword">void</span> bar&lt;<span class="hljs-keyword">int</span>&amp;,<span class="hljs-keyword">double</span>,<span class="hljs-built_in">std</span>::<span class="hljs-built_in">string</span>&gt;(
         <span class="hljs-keyword">int</span>&amp; args_1,
         <span class="hljs-keyword">double</span>&amp;&amp; args_2,
         <span class="hljs-built_in">std</span>::<span class="hljs-built_in">string</span>&amp;&amp; args_3)
{
  foo(<span class="hljs-built_in">std</span>::forward&lt;<span class="hljs-keyword">int</span>&amp;&gt;(args_1),
      <span class="hljs-built_in">std</span>::forward&lt;<span class="hljs-keyword">double</span>&gt;(args_2),
      <span class="hljs-built_in">std</span>::forward&lt;<span class="hljs-built_in">std</span>::<span class="hljs-built_in">string</span>&gt;(args_3));
}
</code></pre>
<p>&#x8FD9;&#x6837;&#x5C31;&#x5C06;&#x7B2C;&#x4E00;&#x4E2A;&#x53C2;&#x6570;&#x4EE5;&#x5DE6;&#x503C;&#x5F15;&#x7528;&#x7684;&#x5F62;&#x5F0F;&#xFF0C;&#x6B63;&#x786E;&#x7684;&#x4F20;&#x9012;&#x7ED9;&#x4E86;foo&#x51FD;&#x6570;&#xFF0C;&#x5176;&#x4ED6;&#x4E24;&#x4E2A;&#x51FD;&#x6570;&#x90FD;&#x662F;&#x4EE5;&#x53F3;&#x503C;&#x5F15;&#x7528;&#x7684;&#x65B9;&#x5F0F;&#x4F20;&#x5165;&#x7684;&#x3002;</p>
<p>&#x6700;&#x540E;&#x4E00;&#x4EF6;&#x4E8B;&#xFF0C;&#x53C2;&#x6570;&#x5305;&#x4E2D;&#x4F7F;&#x7528;<code>sizeof...</code>&#x64CD;&#x4F5C;&#x53EF;&#x4EE5;&#x83B7;&#x53D6;&#x7C7B;&#x578B;&#x53C2;&#x6570;&#x7C7B;&#x578B;&#x7684;&#x5927;&#x5C0F;&#xFF0C;<code>sizeof...(p)</code>&#x5C31;&#x662F;p&#x53C2;&#x6570;&#x5305;&#x4E2D;&#x6240;&#x5305;&#x542B;&#x5143;&#x7D20;&#x7684;&#x4E2A;&#x6570;&#x3002;&#x4E0D;&#x7BA1;&#x662F;&#x7C7B;&#x578B;&#x53C2;&#x6570;&#x5305;&#x6216;&#x51FD;&#x6570;&#x53C2;&#x6570;&#x5305;&#xFF0C;&#x7ED3;&#x679C;&#x90FD;&#x662F;&#x4E00;&#x6837;&#x7684;&#x3002;&#x8FD9;&#x53EF;&#x80FD;&#x662F;&#x552F;&#x4E00;&#x4E00;&#x6B21;&#x5728;&#x4F7F;&#x7528;&#x53C2;&#x6570;&#x5305;&#x7684;&#x65F6;&#x5019;&#xFF0C;&#x6CA1;&#x6709;&#x52A0;&#x7701;&#x7565;&#x53F7;&#xFF1B;&#x8FD9;&#x91CC;&#x7684;&#x7701;&#x7565;&#x53F7;&#x662F;&#x4F5C;&#x4E3A;<code>sizeof...</code>&#x64CD;&#x4F5C;&#x7684;&#x4E00;&#x90E8;&#x5206;&#xFF0C;&#x6240;&#x4EE5;&#x4E0D;&#x7B97;&#x662F;&#x7528;&#x5230;&#x7701;&#x7565;&#x53F7;&#x3002;</p>
<p>&#x4E0B;&#x9762;&#x7684;&#x51FD;&#x6570;&#x4F1A;&#x8FD4;&#x56DE;&#x53C2;&#x6570;&#x7684;&#x6570;&#x91CF;&#xFF1A;</p>
<pre><code class="lang-c++"><span class="hljs-keyword">template</span>&lt;<span class="hljs-keyword">typename</span> ... Args&gt;
<span class="hljs-function"><span class="hljs-keyword">unsigned</span> <span class="hljs-title">count_args</span><span class="hljs-params">(Args ... args)</span>
</span>{
  <span class="hljs-keyword">return</span> <span class="hljs-keyword">sizeof</span>... (Args);
}
</code></pre>
<p>&#x5C31;&#x50CF;&#x666E;&#x901A;&#x7684;sizeof&#x64CD;&#x4F5C;&#x4E00;&#x6837;&#xFF0C;<code>sizeof...</code>&#x7684;&#x7ED3;&#x679C;&#x4E3A;&#x5E38;&#x91CF;&#x8868;&#x8FBE;&#x5F0F;&#xFF0C;&#x6240;&#x4EE5;&#x5176;&#x53EF;&#x4EE5;&#x7528;&#x6765;&#x6307;&#x5B9A;&#x5B9A;&#x4E49;&#x6570;&#x7EC4;&#x957F;&#x5EA6;&#xFF0C;&#x7B49;&#x7B49;&#x3002;</p>

                                
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